488 Battery Voltage Readings

Normal, both my 488 spider and Portofino do the same!

 

With a fully charged Interstate battery, typically low 12's (on accel) to low 14's (on decel) will be realized. With an OEM Ferrari battery reading high 11's to mid 13's, be prepared for a failure. I would replace the battery ASAP and also carry a portable jump starter.

 

Don't have experience with the OEM Ferrari bat, I replaced it the moment I took delivery. Same as Joe I'm seeing low 12s to low 14s is what I'm seeing on my aftermarket Odyssey, for whatever reason it varies quite a bit from accel to decel as mentioned. On my 911 it usually stays at high 13s to mid 14s

probably a good call!

 

Interesting.....my 458 Spider voltage will go between 13v to just over 14v during a drive. I agree with Viperjoe and you obviously felt the same way about replacing the battery.

 

It's probably not the battery. It's something to do with the logic Ferrari used in the 488 vs. the 458 I believe.

In the 458, the charging system seems to function more like any old car would - the alternator puts out max voltage and then a regulator controls it. This is probably why you see 13 to 14 volts with the 458. It's also why the charging system of the 458 charges up the Braille battery fully, whereas the 488 doesn't quite get it.

With the 488, the voltage ranges all over the place. I suspect that Ferrari has done something where the car attempts to reduce the demand on the alternator, based on some logic with the RPM's, charging system output and battery needs (or something crazy along those lines). My guess is that placing less demand on the alternator frees up engine HP, whenever the ECU deems that the charging system doesn't require any voltage much over 12.x or so.

All I know is the i48CS battery worked flawlessly in my 458 and yet in the 488 it could never obtain a 100% charge (and thus required occasional topping off).

This is all just based on seat of the pants driving, practical experience and what I suspect is going on - so I could be totally wrong on some of these points.

BTW, if you have a digital volt meter, it's easy enough to check the state of your car battery. Just check the terminals and read the voltage, then reference this chart:

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This is for a standard battery. The cell voltage on a lithium Ion battery is going to be different. Typically a fully charged, standard car battery will show around 12.70 to 12.75 volts when all is well and the battery is fully charged. If you drive your car and come home, you should be seeing 12.70 all day long. If you check the next couple of days (with the car's ECU drawing away), it's going to be lower of course, but you shouldn't be seeing readings down much below about 12.45 to 12.50 volts usually on a healthy battery.

Ray

 

Actually thought about the same thing (i.e. differences in charging strategy between 458 and 488), so thanks for posting the information. Although 11V seems low when driving, but who knows?

 

It's a function of the "Smart Alternator". It minimizes the parasitic power loss by essentially decoupling the alternator (electronically or mechanically, I'm not sure) when under power.

 

If I was President of Ferrari, S.p.A., the first thing I would do tomorrow morning, when I arrived at the office, is fire the people who came up with this Smart Alternator idea.

Ray

 

Yeah, that's no joke. I have a funny video on YouTube showing installing a battery into my 488. The 458 was a lot more straight forward.

Ray

 

One word: F12. Then tell me about it.